A conventional virtualization device in communication with a data storage array is able to present a logical unit of storage (LUN) on that array to a computerized host device. Additionally, the conventional virtualization device is able to transparently migrate the LUN from one array to another.
For example, suppose that a first array indicates that it is capable of providing a first response time, and that a second array indicates that it is capable of providing a second response time which is faster than the first response time. In such a situation, the conventional storage virtualization device can migrate a LUN from the first array to the second array in an attempt to improve response time to the LUN.